Anemometer



Sept. 29, 1942. E. ARDELT ANEMOMETER Filed Jan. 13, 1941 ELT.,

A TTOR/VE Y.

Patented Sept. 29, 1942 This invention relates; tg an nanometer .and has fr its principal jt'tlie .provision 'i .al highly ecient 21nd alil'i YC'e f ,delle nii-1'1- ing the velocity of flow o f astrea'in of air,l gas', or mnd; ,or the velocity v,or movement of a' b'dy through air, gas,or fluid... ,Y l l v l.

It is ymore particularly desiredad willi-)e .dscribed as anair speed indie "tcuIcr.use.onA aire planes and the like to determine th'e speed .at whichthecraft is' travelingthroughvthe surf` rounding air.A oiject, of the, inveniiqnisto' provide anl accurate airsped indicator which will not beeffected byhm'oistr yfreefzliilg air.V A Aother objecp'safijd' advantages reside in the de-` tail construction of 7the inve tion," whichisdsigned for simplicity; eee l 4and effieieiicv. These, wiubecpme isere apparent frm the fo'1' lowingjdes'cription. c.

Irrthe` following detailed., description, ,of the drawing which'forn'is a p'art hereof. Like numerals refer to like parts in all views of the drawing and throughout' the description.

In the drawing:

Fig. 1 is a face view of the improved anemometer;

Fig. 2 is a cross section therethrough, taken on the line 2-2, Fig. 1;

Fig. 3 is a sectional View, taken on the line 3 3, Fig. 2;

Fig. 4 is a sectional View, taken on the line 4 4, Fig. 2; and

Fig. 5 is a detail section, taken on the line 5 5, Fig. 3.

The invention is mounted in an outer housing .l

I0 having an open face in which a circular frame I I is threaded or otherwise secured. A glass face plate I2 is secured to the frame by means of a suitable slip ring I3.

A cylindrical air chamber I4 is fitted into a cupped depression I5 in the housing I0. A dial plate I6 is secured over the an` chamber I4 in any desired manner, such as by means of suitable screws I1 to completely seal the chamber.

A hand shaft I8 extends axially through the chamber I4 and is journalled therein between a shoulder jewel I9 and an adjustable jeweled bearing screw 2U. The outer extremity of the shaft I8 is reduced in diameter and projects through the jewel I9 beyond the face of the dial plate I 6 where it supports an index hand 2 I A pressure vane 22 is secured to and projects radially from the shaft I8 Within the air chamber I4. This vane is of a size to completely fill inventiqii `referente is haute the accompanying if Iberia.l These sie throfugh the y I t can bere yrseen if air enters ,theport 24 it will act against the ause thelatter to retatetbe Shaft lin is, reiiimed ie'ztheeth @essere ierelieved The epringie da ma are any@ is sured atene .extremity to the dial plate and at the other extremity to the. rl'eieetiag .Perienei thetandeheft Thesis hergledilieei. the. ehamber.- 1,4 through ar` plurality okfrexceedingly small oriiices er. Slets 29,791.1?011 an angleterre ra' as the rane. .2,2. sv'r,.. a. individually and progressively opened throughout their lengths. It will be noted that the further the vane swings, the greater will be the length of the slot which will be exposed and, as the vane leaves one slot it will immediately begin to expose the next successive slot. Thus, wc have the effect of a single continuous slot extending completely around the pressure chamber but by placing the slots at angles, as illustrated, a greater total length of slot is obtained.

Thus, it can be seen that .the vane 22 Will automatically open a suiiicient length of aperture to maintain a constant, predetermined pressure in the chamber. Should the velocity of incoming air increase, the pressure against the vane will increase and the vane will move a proportional amount to increase the area of discharge until the pressure against the vane resumes its original pressure, plus a slight increase to accommodate a slight increased spring reaction. Thus, the vane will move in proportion to the amount of incoming air at all peripheral positions.

The face of the dial plate I6 is calibrated with suitable index numerals 29 to indicate the proper positions of the hand 2| at differing air speeds. The air discharging from the chamber I4 exits from the housing I0 through suitable discharge ports 30 'and may, if desired, be conducted away through a suitable discharge conduit.

The device may be provided with adjusting t means so that it can be pre-set and pre-adjusted the chamber I4 and act as a rotary piston there- 55 to accommodate any desired conditions, and as illustrated, this is accomplished by placing valve ihemiihey .will be blocks 3| in suitable guide channels 32 along each of the :orice slots 28 on the outer face of the chamber I4. These blocks can be moved along their channels to adjust the amount of effective slot area and when finally adjusted can all be locked in place by means of a clamp ring 33 which is secured to the outer face of the chamber I4 by means of suitable clamp screws 34.

It is believed that the various uses of the device are readily apparent. In an aircraft, for instance, the airA conductor 25 would be lead to a position where its intaking extremity would be directed forwardly into the air stream of the Y craft so that the air would flow directly therein to the chamber I4.

One advantage that has been found with this device is that it is self-cleaning, moisture-proof and non-freezing.

In a pressure .-actuated anemometer, of the diaphragm type, the air does not flow through the instrument therefore it is a quiescentor static condition which allows the moisturejthereon to freeze onto the interior 'of the tube'and instrument so as to affect the accuracy thereof. In this instrument, however, the air is constantly flowing freely throughV the instrumentiso that the moisture is carried entirely through and does notcollect. VIt appears that any condensation or freezing occurs on the exV terior of the instrument, whereas on the usual type it occurs on the interior.

While a specific form of the improvement has I been described and illustrated herein, it is desired to be understood that the same may be varied; within the scope of the appended claims,l without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is: 1. An anemometer comprising: a circular pressure chamber; an axially positioned shaft in said chamber; indicating means operable by said shaft; a vane projecting from said shaft and acting as a partition in said chamber; means'for introducing a uid under pressure on one side of said vane; a plurality of slots formed through the wall of said chamber, said slots being in- Yfor introducing a fluid under pressure on one side of said vane; a plurality of slots formed through the wall of said chamber, said slots being incli'ned away from the radii of said chamber so Ythat their effective lengths will increase as Said vane moves away from the introducing means; an individual slide valve for each of said slots; means for guiding each slide valve along its respective slot to control the effective length thereof; and means for locking said slide valves in their adjusted positions.

3. Anv anemometer comprising: a circular pressure chamber; an axially positioned shaft in said chamber; indicating means operable by said shaft; a vane projecting from saidshaft and acting as a partition in said chamber; means for introducing a fluid under pressure on one sideof said vane; V'a plurality of slots formed through the wall of said chamber, said slots being inclined away from the radii of said chamber so that Vtheir effective lengths will increase as said vane moves away from the introducing means; an individual slide valve movable along each slot to control the effective length thereof; an annular clamping member overlying all of said slide valves; and means for clamping said clamping member against said slide valves to lock the latter intheir adjusted positions.

EUGENE M. ARDELT. 

